tests: Re-introduce stat/lstat mocks on macOS
tests: Re-introduce stat/lstat mocks on macOS

Commit d6b17edd5163 ("tests: Lookup extended stat/lstat in mocks")
adds support for mocking of stat() and lstat() on macOS.

The change was broken because virmockstathelpers.c only follows glibc
logic and MOCK_STAT and MOCK_LSTAT are not getting defined on macOS.

Signed-off-by: Roman Bolshakov <e9c94dff02085feaa10f4659102d5bd952cb2e61@yadro.com>
Reviewed-by: Michal Privoznik <83d82aaba2eed257f4814b0c239c260c4caaadf0@redhat.com>

crobinso/libvirt,crobinso/libvirt,libvirt/libvirt,jardasgit/libvirt,zippy2/libvirt,olafhering/libvirt,nertpinx/libvirt,crobinso/libvirt,zippy2/libvirt,olafhering/libvirt,zippy2/libvirt,jardasgit/libvirt,jfehlig/libvirt,libvirt/libvirt,olafhering/libvirt,libvirt/libvirt,nertpinx/libvirt,libvirt/libvirt,jfehlig/libvirt,nertpinx/libvirt,jardasgit/libvirt,olafhering/libvirt,jfehlig/libvirt,crobinso/libvirt,jfehlig/libvirt,jardasgit/libvirt,jardasgit/libvirt,nertpinx/libvirt,nertpinx/libvirt,zippy2/libvirt